1. Technical Field
The present invention relates to methods and apparatuses for treating mixtures, such as agricultural or industrial waste streams, with ultrasonic energy to clean or otherwise alter the waste streams.
2. Background
Many industrial, municipal and agricultural processes generate waste matter that is potentially harmful to the environment. Accordingly, a variety of processes have been developed to remove harmful elements from the waste matter before returning the water to lakes, streams and oceans. Many conventional processes include filters, such as reverse osmosis filters that remove solid contaminants from the waste matter. However, because of environmental concerns, it may be difficult to dispose of the solid contaminants removed by the filters. Furthermore, the filters themselves must be periodically back-flushed, which can be a time consuming process. Accordingly, in one alternative process, microorganisms are disposed in the waste matter to consume or alter harmful elements in the waste matter. However, such systems generally process the waste matter in a batch mode and accordingly may be slow and labor intensive to operate. Another conventional approach is to sterilize waste matter streams with ultraviolet light. One problem with this approach is that the waste matter must be positioned very close to the light source, which can make ultraviolet systems slow, expensive and inefficient. Still another method includes exposing the waste matter stream to ozone, which can alter harmful elements in the waste matter stream. One problem with this approach is that the cost of generating effective quantities of ozone is generally so high that the process may not be economically feasible.
Yet another conventional approach is to expose the waste matter stream to ultrasonic energy. For example, one conventional method includes disposing the waste matter in a vessel and applying ultrasonic energy to the waste matter in a batch process. This conventional approach suffers from several drawbacks. For example, the batch process can be relatively slow. Furthermore, the efficiency with which ultrasonic energy is transmitted to the waste matter may be so low as to leave an unacceptable level of contaminants in the waste matter stream.